The New York Times has published a front-page article raising questions about the past fortune amassed in coal by green billionaire and liberal campaign donor Tom Steyer. The Times' article adds mainstream legitimacy to the mounting GOP attacks on Steyer, who is pledged to spend $100 million on environment campaigns through this November's election. The Times' story, which quotes Australian environmentalists as angry over Steyer's alleged hypocrisy, leaves questions which Steyer will be pressured to answer.

Steyer has divested his massive holdings in a global coal empire to lead a campaign to promote renewable resources and conservation. He is spending millions in defense of President Barack Obama's new regulations to drastically cut emissions from coal plants. He spent $25 million in the 2010 California election cycle to protect the state's historic climate change law. The question is whether Republicans and fossil fuel industry critics can find evidence of anything more serious than Steyer's previous coal investments made through his Farallon Capital Management.

Environmental critics in Australia are demanding that Farallon step away from its backing of the plant at Maules Creek, a facility scheduled to start operations next year and spew coal for three decades. Steyer, according to the Times, sold his ownership stake in Farallon in 2012, "but he has not cut his ties with it entirely," making him a passive investor.

Steyer is well regarded in the environmental movement and valued at the Obama White House. His new endeavor, NextGen Climate, is critical to the climate change movement. He is expected to clarify whether he opposes the coal operations undertaken while at Farallon and end any speculation over his lingering ties.